Police are appealing for witnesses after youths tried to set a woman’s hair on fire as she sat in a train.

The woman was inside a carriage on the 5.17pm Greater Anglia train from Liverpool Street to Shenfield.

Det Con Adam Fairweather, the investigating officer, said: “The victim, a 46-year-old woman from Romford, had boarded the service at Liverpool Street alone.

“She took a seat close to the doors in one of the middle carriages and noticed three young men board the train when it arrived at Stratford.

“A couple of minutes later, the victim could smell burning.

“When she turned to look she realised the boys had been trying to set her hair alight.

“Worried for her own safety, the victim chose not to challenge the youths after another passenger told them to stop what they were doing and move away.”

The three boys left the service when it arrived at Romford around 5.40pm.

The victim stayed on the train and reported the incident to police when she arrived at Harold Wood.

The Liverpool Street to Shenfield service stops at a number of stations, including Ilford, Seven Kings, Goodmayes and Chadwell Heath.

Det Con Fairweather added: “This type of behaviour is dangerous, cruel and totally unacceptable and I am determined to catch those responsible.

“If you were on the train and saw anything, or if you noticed this group anywhere in the vicinity of Romford rail station on February 6, please contact us as a matter of urgency.”

The group is described as three boys, all white, aged between 12 and 14 years old.

The first was approximately 4ft 11in tall and chubby.

He was wearing red tracksuit bottoms with a Nike tick and a black hooded bodywarmer.

The second was approximately 5ft 6in and slim.

He was wearing a grey jumper and tracksuit bottoms.

The third was shorter than the other two and small.

He was wearing an orange hooded jacket.

Anyone with information can call the British Transport Police on 0800 405 040, quoting reference B5/LNA of 17/02/2012, or call Crimestoppers anonymously on 0800 555 111.